	@media screen and (min-width:1200px) {
	  html {
	    font-size: 20px;
	  }
	}

	@media screen and (min-width:800px) and (max-width:1200px) {
	  html {
	    font-size: 16px;
	  }
	}

	@media screen and (max-width:800px) {
	  html {
	    font-size: 12px;
	  }
	}

	* {
	  margin: 0;
	  padding: 0;
	  box-sizing: border-box;
	}

	html,
	body {
	  width: 100%;
	  height: 100%;
	  font-family: '楷体';
	}

	.main {
	  width: 20rem;
	  height: 10rem;
	  display: block;
	  position: fixed;
	  top: 50%;
	  left: 50%;
	  transform: translate(-50%, -50%);
	  background: #E4E7ED;
	  border-radius: 6px;
	}

	.main>p {
	  width: 100%;
	  height: 3rem;
	  text-align: center;
	  line-height: 3rem;
	  background: #409EFF;
	  color: white;
	  border-radius: 6px;
	  border-bottom-right-radius: 0;
	  border-bottom-left-radius: 0;
	}

	.container {
	  display: inline-block;
	  cursor: pointer;
	  margin: 2rem 9rem;
	}

	.bar1,
	.bar2,
	.bar3 {
	  width: 35px;
	  height: 5px;
	  background-color: #333;
	  margin: 6px 0;
	  transition: 0.4s;
	}

	.change .bar1 {
	  -webkit-transform: rotate(-45deg) translate(-9px, 6px);
	  transform: rotate(-45deg) translate(-9px, 6px);
	}

	.change .bar2 {
	  opacity: 0;
	}

	.change .bar3 {
	  -webkit-transform: rotate(45deg) translate(-8px, -8px);
	  transform: rotate(45deg) translate(-8px, -8px);
	}